The present invention relates to ultra-high frequency (UHF) filters and more particularly to a dielectric resonator UHF filter tunable in a large band width.
UHF transmission equipment, e.g. for military purposes, increasingly has to work successively on a number of tuning frequencies. Moreover, fixed frequency civil transmission equipment can also be constructed on the base of standard tunable components, tuning to the fixed working frequency being determined on site by regulating these tunable standard components. The need to produce such tunable components, particularly ultra-high frequency filters, has made it necessary to develop tuning methods such that the filter retains clearly defined characteristics in a tuning band width which is as large as possible in order to cover with a given standard component a wide frequency band, without the characteristics of the component being impaired in said tuning band and in particular the filter response curve, the overvoltage coefficient, coupling, etc.